Patient: What does commensal perineal flora mean on a urine test?
Doctor: When commensal flora are present in the urine up to certain limit, it does not have any significance since it is normal. Female genital tract and perineal area (area around genital and anal region) is commonly colonized by certain microorganisms (Gardnerella vaginalis, Lactobacilli and group B streptococci etc.) which are called commensals. While collecting the urine sample, these organisms my spill into it; hence urine sample should be collected at mid stream to avoid such contamination.